1. Field of Invention
The present invention relates generally to the field of database systems. More specifically, the present invention is related to the reorganization of logically related LOB table spaces.
2. Discussion of Prior Art
A database consists of sets (or tables) of records (or rows) consisting of individual data fields (or columns). LOBs (large objects) are one class of data types that are stored in a database. There are three types of LOBs: (a) character large objects —CLOBs; binary large objects —BLOBs; and double byte character large objects—DBCLOBs. LOB table spaces consist of a base table space and one or more auxiliary tables which each have their own table space. In current database systems, the base table space and the auxiliary table space are reorganized independently.
The following references provide a general teaching in the area of databases and reorganization, but they fail to provide for the limitations of the present invention's system and method.
The U.S. Pat. No. 5,842,208 to Blank et al. provides for a high performance recover/build index system based upon unloading databases files in parallel. The recover/build index system builds a database index for a database file by scanning partitions of the database file in parallel to retrieve key values and their associated record identifier (rid) values. The recover/build index system then sorts the scanned key/rid values for each partition in parallel. Next, the recover/build index system performs one or more merges on the sorted key/rid values from all of the partitions to generate a single key/rid value stream. Finally, the recover/build index system builds the index using the single key/rid value stream.
The U.S. Pat. No. 6,038,569 to Beavin et al. provides for a system for data structure loading with concurrent image data. After data records are obtained from one or more data sources, each of the data records is associated with one of multiple pages. As each page is completed, it is written to a primary data structure. Partially or completely failed primary data structures may also be restored using image copies made previously.
The U.S. Pat. No. 6,535,895 to Bonner et al. provides for a technique to avoid processing well clustered LOB's during reorganization of a LOB table space. A table space is reorganized in a database stored on a data storage device connected to a computer. When inserting or updating a LOB into a portion of the table space, a space map is marked to indicate whether the LOB was well inserted. When reorganizing the table space, when the space map indicates that a LOB was well inserted, reorganization of the portion of the table space in which the LOB was well inserted is avoided. U.S. Pat. No. 6,606,617 and U.S. patent publication No. 2002/0065792, both by Bonner et al., provide for a similar teaching.
The U.S. Pat. No. 6,237,003 to Lewish et al. provides for a method and apparatus for supporting dynamic run-time object definition in a relational database system. A mediating layer is introduce between the applications and the database objects.
The U.S. application publication to Chen et al. (2002/0138497) discloses the implementation of a database trigger that automatically executes a set of SQL statements whenever a specified event occurs. The trigger could be reading or updating a database or perform other functions. The database is programmed to allow a large object (LOB) data to be stored with transition variables. A base table appears to comprise a database having a row identifier (“row”ID) and one or more non-large object columns and large object and large object (LOB) tables. RowID and version are used to access the LOB data in an auxiliary table.
The IBM TDB (Vol. 33, No. 7, December 1990, pp 177–180) entitled “Browsing: A novel facility for exploring the contents of a datastore” discloses a method for navigating from a data element to related data elements, wherein the data elements may be related to other data elements of the same class (or another class) by named relationships.
Whatever the precise merits, features, and advantages of the above cited references, none of them achieves or fulfills the purposes of the present invention.